This is the first in a Daily Caller investigative series on Media Matters For America. Daily Caller reporters Alex Pappas and Will Rahn contributed to this report.

David Brock was smoking a cigarette on the roof of his Washington, D.C. office one day in the late fall of 2010 when his assistant and two bodyguards suddenly appeared and whisked him and his colleague Eric Burns down the stairs.

Brock, the head of the liberal nonprofit Media Matters for America, had told friends and co-workers that he feared he was in imminent danger from right-wing assassins and needed a security team to keep him safe.

The threat he faced while smoking on his roof? “Snipers,” a former co-worker recalled.

“He had more security than a Third World dictator,” one employee said, explaining that Brock’s bodyguards would rarely leave his side, even accompanying him to his home in an affluent Washington neighborhood each night where they “stood post” to protect him. “What movement leader has a detail?” asked someone who saw it.

Extensive interviews with a number of Brock’s current and former colleagues at Media Matters, as well as with leaders from across the spectrum of Democratic politics, reveal an organization roiled by its leader’s volatile and erratic behavior and struggles with mental illness, and an office where Brock’s executive assistant carried a handgun to public events in order to defend his boss from unseen threats.

Yet those same interviews, as well as a detailed organizational planning memo obtained by The Daily Caller, also suggest that Media Matters has to a great extent achieved its central goal of influencing the national media.

Founded by Brock in 2004 as a liberal counterweight to “conservative misinformation” in the press, Media Matters has in less than a decade become a powerful player in Democratic politics. The group operates in regular coordination with the highest levels of the Obama White House, as well as with members of Congress and progressive groups around the country. Brock, who collected over $250,000 in salary from Media Matters in 2010, has himself become a major fundraiser on the left. According to an internal memo obtained by TheDC, Media Matters intends to spend nearly $20 million in 2012 to influence news coverage.

Donors have every reason to expect success, as the group’s effect on many news organizations has already been profound. “We were pretty much writing their prime time,” a former Media Matters employee said of the cable channel MSNBC. “But then virtually all the mainstream media was using our stuff.”

The group scored its first significant public coup in 2007 with the firing of host Don Imus from MSNBC. Just before Easter that year, a Media Matters employee recorded Imus’s now-famous attack on the Rutgers women’s basketball team, and immediately recognized its inflammatory potential. The organization swung into action, notifying organizations like the NAACP, the National Association of Black Journalists, and Al Sharpton’s National Action Network, all of which joined the fight.

Over the course of a week, Media Matters mobilized more than 50 people to work full-time adding fuel to the Imus story. Researchers searched the massive Media Matters database for controversial statements Imus had made over the years. The group issued press release after press release. Brock personally called the heads of various liberal activist groups to coordinate a message. By the end of the week, Imus was fired.

Media Matters soon became more sophisticated in its campaigns against non-liberal cable news anchors. Lou Dobbs, then of CNN, was a frequent target.

“As part of the Drop Dobbs campaign,” explains one internal memo prepared for fundraising, “Media Matters produced and was prepared to run an advertisement against Ford Motor Company on Spanish Language stations in Houston, San Antonio, and other cities targeting its top selling product, pick-up trucks, in its top truck buying markets.”

Ford pulled its advertising from Dobbs’s program before the television ad aired, but Media Matters kept up its efforts, working primarily with Alex Nogales of the National Hispanic Media Coalition, and with the League of United Latin American Citizens, the Mexican American Legal Defense and Educational Fund and other self-described civil rights groups.

In November of 2009, Dobbs left CNN. “We got him fired,” says one staffer flatly.

“Certainly Media Matters deserves a lot of credit for the work they did,” Nogales said in an interview. “They’re very effective.”

Glenn Beck, the former Fox News Channel host, drew the ire of a wide spectrum of liberal groups while his program aired nationally. But according to several people who watched the process from the inside, it was Media Matters that orchestrated much of the opposition to Beck.

“We called it ‘fingerprint coverage,’” explains one former staffer, “where you know it was the result of your work.” As an example, he cites the left-wing group Color of Change, co-founded by the controversial former White House “green jobs” czar Van Jones, which received much of the credit for pressuring advertisers to drop their sponsorship of Beck’s show. But in fact, he says, Media Matters developed the campaign that cowed Beck’s sponsors.

Media Matters, according to its 2010 tax filing, gave a $200,000 grant to Citizen Engagement Laboratory, Color of Change’s parent group. The purpose of the grant, according to the document, was for a “campaign to expose Glenn Beck’s racist rhetoric in an effort to educate advertisers about the practices on his show.”

High profile though these victories against conservatives were, Media Matters has perhaps achieved more influence simply by putting its talking points into the willing hands of liberal journalists. “In ‘08 it became pretty apparent MSNBC was going left,” says one source. “They were using our research to write their stories. They were eager to use our stuff.” Media Matters staff had the direct line of MSNBC president Phil Griffin, and used it. Griffin took their calls.

Stories about Fox News were especially well received by MSNBC anchors and executives: “If we published something about Fox in the morning, they’d have it on the air that night verbatim.”

But MSNBC executives weren’t the only ones talking regularly to Media Matters.

“The HuffPo guys were good, Sam Stein and Nico [Pitney],” remembered one former staffer. “The people at Huffington Post were always eager to cooperate, which is no surprise given David’s long history with Arianna [Huffington].”

“Jim Rainey at the LA Times took a lot of our stuff,” the staffer continued. “So did Joe Garofoli at the San Francisco Chronicle. We’ve pushed stories to Eugene Robinson and E.J. Dionne [at the Washington Post]. Brian Stelter at the New York Times was helpful.”

“Ben Smith [formerly of Politico, now at BuzzFeed.com] will take stories and write what you want him to write,” explained the former employee, whose account was confirmed by other sources. Staffers at Media Matters “knew they could dump stuff to Ben Smith, they knew they could dump it at Plum Line [Greg Sargent’s Washington Post blog], so that’s where they sent it.”

Smith, who refused to comment on the substance of these claims, later took to Twitter to say that he has been critical of Media Matters.

Reporters who weren’t cooperative might feel the sting of a Media Matters campaign against them. “If you hit a reporter, say a beat reporter at a regional newspaper,” a Media Matters source said, “all of a sudden they’d get a thousand hostile emails. Sometimes they’d melt down. It had a real effect on reporters who weren’t used to that kind of scrutiny.”

A group with the ability to shape news coverage is of incalculable value to the politicians it supports, so it’s no surprise that Media Matters has been in regular contact with political operatives in the Obama administration. According to visitor logs, on June 16, 2010, Brock and then-Media Matters president Eric Burns traveled to the White House for a meeting with Valerie Jarrett, arguably the president’s closest adviser. Recently departed Obama communications director Anita Dunn returned to the White House for the meeting as well.

It’s not clear what the four spoke about — no one in the meeting returned repeated calls for comment — but the apparent coordination continued. “Anita Dunn became a regular presence at the office,” says someone who worked there. Then-president of Media Matters, Eric Burns, “lunched with her, met with her and chatted with her frequently on any number of matters.”

Media Matters also began a weekly strategy call with the White House, which continues, joined by the liberal Center for American Progress think tank. Jen Psaki, Obama’s deputy communications director, was a frequent participant before she left for the private sector in October 2011.

Every Tuesday evening, meanwhile, a representative from Media Matters attends the Common Purpose Project meeting at the Capitol Hilton on 16th Street in Washington, where dozens of progressive organizations formulate strategy, often with a representative from the Obama White House.

In the past several years, Media Matters has focused much of its considerable energy on the Fox News Channel. The network, declares one internal memo, “is the de facto leader of the GOP and it is long past time that it was treated as such by the media, elected officials, and the public.” At the end of September 2009, Burns made the case publicly in an interview on MSNBC.

Fox, he said, “is a political organization, and their aim is to destroy a progressive policy agenda.”

Less than a month later, in language that could have been copied directly from a Media Matters press release, White House communications director Anita Dunn leveled almost precisely the same charge, dismissing Fox as “more a wing of the Republican Party.”

Were the lines of attack coordinated? “To my knowledge, there wasn’t coordination,” says a source. But at times there has seemed to be a kind of mind meld between the Obama political team and Media Matters.

During the 2008 presidential campaign, for example, author Jerome Corsi wrote a highly critical book about the Democratic candidate, titled “The Obama Nation.” The Obama campaign responded immediately with a detailed memo. The title of that memo, “Unfit For Publication” (a play on Corsi’s 2004 book, “Unfit for Command,” about then-presidential candidate Senator John Kerry), was the same title used by Media Matters just weeks before in a similar memo about the same book.

The irony of Brock’s relationship with the White House is that at certain points he has been openly hostile to Barack Obama, especially in conversations in social settings. Described by some who know him as a passionate and emotional Hillary Clinton supporter, many Democrats believe Brock maintained regular contact with the highest levels of Clinton’s campaign and its advisers.

As late as 2010, Brock was still exchanging personal emails with longtime Hillary Clinton consigliore Sidney Blumenthal, in which the two seemed to grouse about Obama and bond over their shared connection to Hillary.

The intensity of the 2008 campaign, say those who knew Brock at the time, seemed to exacerbate his bouts of what appeared to be mania, a condition from which he had apparently suffered for some time. In 2002, the Drudge Report reported that Brock had “suffered a breakdown” the year before and was treated in the psychiatric ward of Sibley Memorial Hospital in Washington.

During a 2008 meeting of the left-wing umbrella group Democracy Alliance outside San Diego, Brock’s unusual behavior drew considerable attention. According to a fellow attendee, “David completely lost his shit. He started getting incredibly aggressive. He alienated important people in the progressive movement, like John Podesta [of the Center for American Progress] and Anna Burger [of the Service Employees International Union]. Lots of drama. There were a lot of conversations about David’s mental health.”

Two years later, at another Democracy Alliance meeting shortly after the 2010 election, Brock behaved in a way one prominent liberal who was there described as “erratic, unstable and disturbing.” Brock’s aggression, this person said, was “hard to ignore and noticed by a number of people,” generating “quite a bit of concern” about his condition. A number of demonstrably odd media appearances Brock made around this time only reinforced those concerns.

All of this, sources say, has caused anxiety for prominent Democrats. Brock’s profile has risen recently, mostly due to American Bridge 21st Century, the political action committee he founded and runs. Brock boasted loudly and in public that American Bridge would be an answer to Karl Rove’s American Crossroads GPS, a claim some found unsettlingly grandiose.

At some point, Brock received a prescription for his condition. “Some days he’d come in and you could tell he was on his meds because he would just sit in his office alone and not engage with staff,” says a coworker. Other days, “he’d be intensely engaged. He’d get manic, very reckless and grandiose. You’d see this level of self-confidence in him that would spiral.”

Last spring, some at Media Matters headquarters and in other parts of the progressive world were caught off guard by an interview Brock gave to Ben Smith at Politico, in which he promised to wage “guerrilla warfare and sabotage” against Fox News. “It was insane,” says a coworker. “David was totally manic at the time. We were all shocked.”

Friends say Brock, who has publicly admitted drug use in the past, was working obsessively and staying out late with compatriots. “They’d close [local bars] and party till six in the morning,” said one.

A number of people in Brock’s orbit believe he was regularly using illegal drugs, including cocaine. “It’s not like he was trying to keep it a secret,” says a female friend of Brock’s.

Sources back at the Media Matters offices describe an atmosphere of tension and paranoia. “Many of us lived in fear that at any point we could be fired,” one said. Brock believed he had received credible death threats, and employed a two-man security detail, at least one of whom was armed and acted as his driver. A new security system was installed in his house. He became concerned that one of his bodyguards was plotting against him.

By 2010, Brock’s personal assistant, a man named Haydn Price-Morris, was carrying a holstered and concealed Glock handgun when he accompanied Brock to events, including events in Washington, D.C., a city with famously restrictive gun laws. Price-Morris told others he carried the gun to protect Brock from threats.

Late in 2010, other Media Matters employees learned about Price-Morris’s gun, and he was fired due to their objections. No public announcement was made.

According to one source with knowledge of what happened next, Brock was “terrified” that news of the gun would leak. “George Soros and a lot of groups connected to gun control are funding this group, and they wouldn’t be too happy that an employee of Media Matters was carrying a gun, especially when it was illegal in D.C.”

Meanwhile, Brock became rigid and harsh with his employees — “viciously mean,” in the words of someone who witnessed it. “He spent a lot of time ripping up researchers. It was abusive. I never understood why more people didn’t quit.” One staffer recalls Brock saying he would like to fire a researcher for being physically repugnant. “David definitely does not like ugly people.”

At times, Brock would become crazed with intensity, “obsessively” involving himself in research: “There was a point at which he would pore over every single piece of research we put out, 10 or 15 dense items a day. He would line-item all of it.”

David Saldana, the former deputy editorial director at Media Matters, concedes that under Brock’s leadership, “there were very harsh penalties for getting things wrong. And justifiably so. … There was no room for weakness. Things had to be gotten right.”

The atmosphere in the office was considerably more tolerant on non-editorial matters. “There were these two folks who got caught [having sex] in the communications war room on the weekend,” said one employee.

“People came in, and lo and behold there were two of their colleagues doing the nasty on a desk.” Neither one was fired.